All terrain vehicle with improved air intake

ABSTRACT

An all terrain vehicle contains a partition wall which partitions a passenger space and a hood which is arranged ahead of the partition wall. When viewed from the side of the vehicle, an air outlet of an exhaust passage is opened in an upper space located between the partition wall and the hood.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an all terrain vehicle including an engine and a belt-type continuously variable transmission which varies rotating speeds of the engine to output power, having an improved air intake.

2. Description of Related Art

Generally, an all terrain vehicle with a mounted engine unit having an integrated engine and a belt-type continuously variable transmission includes a cooling unit which supplies cooling air into the continuously variable transmission to cool a belt. As disclosed in U.S. Pat. No. 5,086,858, an engine unit is mounted behind a seat, a cooling air intake port is formed in a front end portion of a transmission case containing the belt-type continuously variable transmission in the engine unit, and a cooling air outlet port is formed in a rear end portion. Air is supplied to the cooling air intake from an upper portion of a pillar frame arranged upright behind the seat, and cooling air is discharged from the cooling air outlet to the rear side of the vehicle.

In the prior art, the cooling air is directly discharged from the cooling air outlet of the transmission case to the rear side of the vehicle. For this reason, exhaust sounds from the outlet can unfortunately be easily transmitted to a passenger sitting on the seat as a harsh noise.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of the prior art, and has as its object to provide an all terrain vehicle which can inhibit exhaust sound from being transmitted to a passenger when cooling air is discharged.

According to an aspect of the present invention, there is provided an all terrain vehicle including: a body frame; a pair of left and right wheels and at least one pair of left and right rear wheels which are supported by the body frame; a partition wall arranged behind the front wheel in a front/rear direction of the vehicle; a seat which is arranged behind the partition wall in the front/rear direction of the vehicle and on which a passenger sits; an engine which is arranged behind the partition wall in the front/rear direction of the vehicle and a belt-type continuously variable transmission which varies rotating speeds of the engine to output power, the engine and the belt-type continuously variable transmission being mounted on the body frame; a hood having at least a part located ahead of the partition wall in the front/rear direction of the vehicle, and located above the front wheel; a cooling air passage which supplies cooling air into the continuously variable transmission; and an exhaust passage which has an air outlet located ahead of at least a part of the partition wall and below the hood and discharges the cooling air from an inside of the continuously variable transmission.

According to the vehicle of the present invention, since an air outlet of an exhaust passage which discharges air which cools the belt-type continuously variable transmission is opened ahead of at least a part of the partition wall and below the hood, exhaust sound from the air outlet is insulated by the partition wall and the hood. Therefore, noise can be inhibited from being transmitted to a passenger.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an all-terrain vehicle according to an embodiment of the present invention;

FIG. 2 is a side view of a body frame on which an engine unit of the vehicle is mounted;

FIG. 3 is a plan view of the body frame;

FIG. 4 is a side view of the engine unit;

FIG. 5 is a plan view of the engine;

FIG. 6 is a plan view of a housing box mounted on the body frame;

FIG. 7 is a side view of the housing box;

FIG. 8 is a perspective view of the housing box; and

FIG. 9 is a plan view showing an arrangement state of a floor, a tunnel portion, an engine unit, and respective passages.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1 to 9 are views to explain an all-terrain vehicle according to an embodiment of the present invention. In the embodiment, front, rear, ahead, behind, left, right, above, and below, unless otherwise noted, are from the perspective of a passenger sitting on a seat. Also, as shown in the Figures like parts are identified with the same numeral. The front wheels are the same on both the left and right sides, so they are referenced by like numeral 3. In some instances only the left side of the vehicle is shown, but it is understood that similar items on the right side, while not shown, are of similar nature.

In the drawings, reference numeral 1 denotes an all-terrain vehicle. The vehicle 1 includes a body frame 2, an engine unit 3 mounted on the body frame 2, front wheels 4 arranged at left and right front ends of the body frame 2, and rear wheels 5 arranged at left and right rear ends.

The body frame 2 includes a main frame 2 a which extends in the front/rear direction of the vehicle to have a ladder-like shape and on which the left and right front wheels 4, the left and right rear wheels 5 and the engine unit 3 are arranged, left and right pillar frames 2 b which are arranged upright on left and right outer ends of a front/rear center portion of the main frame 2 a and which form a vehicle chamber (passenger space) A together with the main frame 2 a, a front frame 2 c which is arranged upright ahead of the vehicle chamber A to configure a front chamber B, and a loading space frame 2 e arranged upright behind the vehicle chamber A.

The main frame 2 a has left and right center members 12 extending in the front/rear direction of the vehicle and front and rear cross members 14 which connect front ends and rear ends of the left and right center members 12 to each other. Middle portions of the left and right center members 12 are connected to each other by planar center cross members 13. The engine unit 3 is mounted on the planar center cross members 13.

Outer ends of the front and rear cross members 14 in the front/rear direction of the vehicle are connected to the pillar frames 2 b.

The pillar frames 2 b have left and right pillar members 15 where front and rear entrances 15 a and 15 b are formed, and a plurality of roof members 16 which connect upper sides of the left and right pillar members 15 to each other.

The front frame 2 c, as shown in FIG. 6 and FIG. 8, has first and second cross frames 45 and 46, first and second center frames 47, and first and second side frames 48. The first cross frame 45 is arranged near the front end of the vehicle chamber A and above the main frame 2 a, and extends in the width direction of the vehicle to connect the left and right pillar members 15, 15 to each other. The second cross frame 46 is arranged ahead of the first cross frame 45 to extend in the width direction of the vehicle. The first and second side frames 48 are arranged to extend in the front/rear direction of the vehicle at a left side portion and a right side portion in the width direction of the vehicle. The first and second center frames 47 extend in the front/rear direction of the vehicle inside the side frame in the width direction of the vehicle and connect the first cross frame 45 to the second cross frame 46. The front ends of the first and second center frames 47 are connected to the front end of the main frame 2 a by left and right stays 47 a.

The loading space frame 2 e has stays 2 f arranged upright near the rear end of the main frame 2 a, side frames 2 g supported by the stays 2 f, and a plurality of cross frames 2 h which connect the side frames 2 g to each other.

A first seat 6 is mounted substantially on a center portion of the main frame 2 a in the front/rear direction of the vehicle, and a second seat 7 is mounted on a front portion of the loading space frame 2 e. A loading space 10 is arranged behind the second seat 7 of the loading space frame 2 e. A first floor 8 is arranged on a forward portion of the first seat 6 of the main frame 2 a.

The first seat 6 is configured by left and right seats 6 a and 6 b arranged with a predetermined gap in the width direction of the vehicle. The engine unit 3 is mounted between the left and right seats 6 a and 6 b.

Each of the left and right seats 6 a and 6 b has a seat cushion 6 c and a seat back 6 d, and a steering wheel 17 is arranged ahead of the left seat 6 a.

The second seat 7 is arranged at a position substantially as high as the first seat 6, and has a bench seat cushion 7 a and a seat back 7 b for two passengers. A headrest 7 c is arranged above the seat back 7 b.

The vehicle 1 includes a partition wall 23 which is arranged behind the front wheels 4 in the front/rear direction of the vehicle to partition the vehicle 1 to form the vehicle chamber A and the front chamber B. The front chamber B is a space in front of the partition wall 23 and below a hood 25. The hood 25 is at least partially located ahead of the partition wall 23 in the front/rear direction of the vehicle, and is located above the front wheels 4. Left and right first floors (footrests) 8 for the passengers to place their feet are arranged between the partition wall 23 and the left and right seats 6 a and 6 b. Between the left and right first floors 8 in the width direction of the vehicle, a console 24 having an interior projects upward extending in the form of a tunnel substantially from the center portion of the partition wall 23 in the width direction of the vehicle to the rear side of the vehicle in the front/rear direction of the vehicle, and communicating with the front chamber B is arranged. An upper end 24 a of the console 24 is arranged at a position slightly higher than a seat level of the first seat 6.

The partition wall 23 is arranged at a front end of the pillar frames 2 b, and has an upper portion 23 a on which gauges (not shown) such as a speedometer are arranged, an intermediate portion 23 b extending diagonally forward from the upper portion 23 a to the lower side, and a lower portion 23 c extending diagonally backward from the intermediate portion 23 b to the lower side. An accelerator pedal and a brake pedal (not shown) are arranged in the lower portion 23 c. Front ends of the first floors 8 are connected to the rear end of the lower portion 23 c.

The engine unit 3 is arranged in the interior space of console 24. The engine unit 3 includes a water-cooled four-cycle engine 20, a V-belt continuously variable transmission 21 which continuously varies a rotating speed of the engine 20, and a cooling unit 28 which cools the continuously variable transmission 21.

The engine 20 is obtained by stacking a cylinder body 20 g and a cylinder head 20 c on a crank case 20 f and connecting the cylinder body 20 g and the cylinder head 20 c to each other. The continuously variable transmission 21 is connected to a side portion of the crank case 20 f.

The engine 20 is arranged on a center portion of the left and right side members 12 in the front/rear direction of the vehicle and between the left and right seats 6 a and 6 b of the first seat 6. A crank shaft 20 a of the engine 20 almost horizontally faces in the width direction of the vehicle, and a cylinder shaft line 20 b faces diagonally backward and upward.

The engine 20 partially overlaps the first seat 6 when viewed from a side of the vehicle. More specifically, the cylinder head 20 c of the engine 20 is arranged to overlap the seat cushion 6 c.

The engine 20 is mounted such that an intake port 20 d opened on a front side wall of the cylinder head 20 c faces the front side of the vehicle and an exhaust port 20 e open on a rear side wall faces the rear side of the vehicle (see FIG. 4).

An intake pipe (intake passage) 30 is connected to the intake port 20 d of the cylinder head 20 c. The intake pipe 30 extends from the intake port 20 d to the front side of the vehicle to supply combustion air into the engine 20. An exhaust pipe (exhaust passage) 31 is connected to the exhaust port 20 e. The exhaust pipe 31 extends from the exhaust port 20 e to the rear side of the vehicle to discharge exhaust gas to the rear side of the vehicle. The intake pipe 30 and the exhaust pipe 31 are almost linearly arranged substantially along a center line of the vehicle in the front/rear direction when viewed from the above.

The exhaust pipe 31 includes a first vertical pipe portion 3 lb almost vertically extending from a connection unit 31 a connected to the cylinder head 20 c to the lower side, a horizontal pipe portion 31 c extending from a lower end of the first vertical pipe portion 31 b to the rear side under a second floor 9, a second vertical pipe portion 31 d extending upright from a rear end of the horizontal pipe portion 31 c to the upper side, and an extending portion 31 e extending from an upper end of the second vertical pipe portion 31 d to the rear side of the vehicle between the second seat 7 and a rear wheel drive shaft 5 a of the rear wheels 5.

The exhaust pipe 31 includes a muffler 36 connected to a rear end of the extending portion 31 e and arranged in the rear of the second seat 7. The muffler 36 has an elliptic shape having a vertical dimension larger than a horizontal dimension, and arranged to have an axial line along the width direction of the vehicle.

The intake pipe 30 is connected to the cylinder head 20 c through a throttle body 32 having a fuel injection valve 33.

In the middle of the intake pipe 30, a surge tank 34 is interposed. The surge tank 34 is arranged ahead of the engine 20 in the tunnel portion 24. An air cleaner 35 is connected to the surge tank 34 through an intake air supply pipe 30 a. The surge tank 34 has a capacity larger than that of the air cleaner 35.

The air cleaner 35 is arranged at a center portion in the width direction of the vehicle and at a portion surrounded by the upper portion 23 a and the intermediate portion 23 b of the partition wall 23 and the hood 25 in the front chamber B in a side view.

The intake port 35 a is connected and formed on a rear wall of the air cleaner 35. The intake port 35 a is located at a position higher than an upper end 4 b of the front wheel 4 and formed in a portion surrounded by the intermediate portion 23 b of partition wall 23 and the hood 25, preferably facing rearward.

The continuously variable transmission 21 has a transmission case 21 a connected to a left side of the engine 20 in the width direction of the vehicle and extending from the engine 20 to the front side, a drive pulley 21 b housed in the transmission case 21 a and attached to the crank shaft 20 a of the engine 20, a driven pulley 21 d attached to an output shaft 21 c which is parallel to the crank shaft 20 a, and a V-belt 21 e wound on the drive pulley 21 b and the driven pulley 21 d.

A front power transmission shaft 22 a extending forward and a rear power transmission shaft 22 b extending backward are connected to the output shaft 21 c. The front and rear power transmission shafts 22 a, 22 b are connected to the front and rear wheel drive shafts 4 a and 5 a through front and rear differential devices 22 c, 22 d, respectively.

The cooling unit 28 includes a cooling air supply duct (cooling air passage) 40 which supplies cooling air into the continuously variable transmission 21, and a cooling air exhaust duct (exhaust passage) 41 which discharges cooling air, and has a structure as described below in detail.

An air inlet port 21 f is formed in a portion, facing the output shaft 21 c, of a left outer side wall of the transmission case 21 a. An air exhaust port 21 g, facing the drive pulley 21 b, is formed in a portion of an upper wall portion. The cooling air supply duct 40 is connected to the air inlet port 21 f, and the cooling air exhaust duct 41 is connected to the air exhaust port 21 g.

On a circumferential surface of the drive pulley 21 b, a large number of fins (not shown) are formed in a circumferential direction. The drive pulley 21 b rotates to take cooling air in the transmission case 21 a.

The cooling air supply duct 40 has a first inlet portion 40 b extending from the air inlet port 21 f and curving to the inside in the width direction of the vehicle, a second inlet portion 40 c extending from the first inlet portion 40 b and passing through a portion below the surge tank 34, a third inlet portion 40 d extending from the second inlet portion 40 c to rise up on a front side of the surge tank 34, and a fourth inlet portion 40 e extending from the third inlet portion 40 d and curving to the right side in the width direction of the vehicle. An air inlet port 40 a is formed in the fourth inlet portion 40 e.

The air inlet port 40 a is located at a position higher than the upper end 4 b of the front wheel 4 and formed near a right side wall of the air cleaner 35 above the front chamber B in the width direction of the vehicle underneath hood 25.

The air inlet port 40 a, as shown in FIGS. 6 to 8, is connected to an air intake port 43 d defined in a housing box 43 which houses in-vehicle parts attached to the front frame 2 c, and has the following structure as described below in detail.

The housing box 43 is arranged at a portion surrounded by the first cross frame 45, the second cross frame 46, the second side frames 48, and the second center frame 47 of the front frame 2 c. The housing box 43 has a housing box body 43 a in which in-vehicle parts such as a battery 49 and various electronic parts 50 are housed, and a housing box cover 43 b attached to the housing box body 43 a to cover the upper side thereof.

An air inhalant port 43 c is formed on a front end of the housing box cover 43 b to open forward, and an air intake port 43 d is formed in a rear end of an inner wall thereof. The air inlet 40 a of the cooling air supply duct 40 is connected to the air intake port 43 d. In this manner, air which has cooled the battery 49 and the electronic parts 50 is supplied into the transmission case 21 a through the cooling air supply duct 40.

The cooling air exhaust duct 41 has a first exhaust portion 41 b extending from the air exhaust port 21 g to be diagonally forward and curved towards the lower side below the intake pipe 30, a second exhaust portion 41 c extending from the first exhaust portion 41 b below the surge tank 34 almost in parallel to the second inlet portion 40 c, a third exhaust portion 41 d extending from the second exhaust portion 41 c to rise up on a front side of the surge tank 34 almost in parallel to the third inlet portion 40 d, a fourth exhaust portion 41 e extending from the third exhaust portion 41 d to be curved to the left side in the width direction of the vehicle, and a fifth exhaust portion 41 f extending from the fourth exhaust portion 41 e and then diagonally backward extending to the lower side. An air outlet 41 a is defined at the end of the fifth exhaust portion 41 f directed downward and rearwardly.

The air outlet 41 a is located at a position higher than the upper end 4 b of the front wheel to open in the upper portion of the front chamber B downward and backward.

The intake pipe 30 and the surge tank 34 are arranged to be positioned above the cooling air supply duct 40 and the cooling air exhaust duct 41.

When viewed from the upper side of the vehicle, the intake pipe 30 partially overlaps the cooling air supply duct 40 and the cooling air exhaust duct 41, and the surge tank 34 partially overlaps the cooling air supply duct 40 and the cooling air exhaust duct 41. The intake pipe 30, the surge tank 34, the cooling air supply duct 40, and the cooling air exhaust duct 41 overlap the console 24 at the same time. More specifically, the intake pipe 30 overlaps the first exhaust portion 41 b, and the surge tank 34 overlaps the second inlet portion 40 c and the second exhaust portion 41 c.

The intake port 35 a of the air cleaner 35 vertically overlaps the third inlet portion 40 d and the third exhaust portion 41 d. The intake air supply pipe 30 a is located between the third inlet portion 40 d and the third exhaust portion 41 d.

The air inlet port 40 a and the air outlet 41 a open in a portion above the front chamber B, the portion being surrounded by the upper portion 23 a and the intermediate portion 23 b of the partition wall 23 and the hood 25. The air inlet port 40 a and the air outlet 41 a are separately arranged on one side and the other side with reference to the center line of the vehicle in the width direction of the vehicle. More specifically, the air inlet port 40 a and the air outlet 41 a are spaced apart from each other with an interval which is ½ or more of the dimension in width of the vehicle.

According to the present embodiment, the air outlet 41 a of the cooling air exhaust duct 41 which discharges air that has cooled the continuously variable transmission 21 is located ahead of the partition wall 23 and below the hood 25. For this reason, exhaust sound from the air outlet 41 a is insulated by the partition wall 23 and the hood 25, and noise caused by exhaust can be inhibited from being transmitted to a passenger sitting in the vehicle chamber A.

Since the air outlet 41 a is opened at a position higher than the upper end 4 b of the front wheel, splashed water and splashed earth and sand caused by the front wheel 4 can be prevented from entering the air outlet 41 a. More specifically, the all terrain vehicle 1 according to the present embodiment may be driven on a river, a marshy place, or earth road where the front wheels 4 and the rear wheels 5 are submerged. When the vehicle is driven on such an uneven ground, water, earth, and sand can be prevented from entering the air outlet 41 a.

Since the air outlet 41 a is opened downward and backward, rain water or water in car wash can be prevented from entering the air outlet 41 a from the above while the splashed water and earth and sand can be prevented from entering the air outlet 41 a.

In the present embodiment, since the air inlet port 40 a of the cooling air supply duct 40 is opened in the upper portion of the front chamber B, suction noise from the air inlet port 40 a is insulated by the partition wall 23 and the hood 25. For this reason, the suction noise can be inhibited from being transmitted to a passenger sitting in the vehicle chamber A.

Since the air inlet port 40 a is opened at a position higher than the upper end 4 b of the front wheel 4, splashed water and splashed earth and sand caused by the front wheels 4 can be prevented from entering the air outlet 41 a.

In the present embodiment, since the air inlet port 40 a is opened in the housing box 43 in which in-vehicle parts such as the battery 49 and the various electronic parts 50 are housed, the in-vehicle parts are cooled when cooling air passes through the inside of the housing box 43, cooling capability of the in-vehicle parts can be improved without providing an additional cooling structure.

In present the embodiment, since the air inlet port 40 a and the air outlet 41 a are separately arranged in the width direction of the vehicle, more specifically, since the air inlet port 40 a and the air outlet 41 a are arranged with an interval which is ½ or more of the dimension in width of the vehicle, high-temperature exhaust air can be reliably prevented from flowing into the air inlet port 40 a. In this manner, low-temperature air can be supplied, and cooling efficiency can be improved.

In the present embodiment, since the intake port 35 a of the air cleaner 35 to which the intake pipe 30 is connected is opened in the upper portion of the front chamber B in a side view, suction noise from the intake port 35 a can be insulated as described above, and the suction noise can be inhibited from being transmitted to a passenger in the vehicle chamber A.

Since the intake port 35 a is opened at a position higher than the upper end 4 b of the front wheel 4, as described above, splashed water and splashed earth and sand caused by the front wheels 4 can be prevented from entering the intake port 35 a.

In the present embodiment, since the engine unit 3 is arranged in the console 24 behind the partition wall 23, for example, heat effect on cooling air or combustion air occurring when an engine is arranged below a hood can be avoided, and low-temperature air can be supplied to the continuously variable transmission 21 and the engine 20.

In the present embodiment, the first seat 6 arranged on the front side of the vehicle and the second seat 7 arranged behind the first seat 6 are arranged, and the V-belt continuously variable transmission 21 is arranged below the first seat 6. For this reason, a seat level can be lowered, and a passenger space for a passenger sitting on the first seat can be secured.

When viewed from the side of the vehicle, the first seat 6 and the engine 20 are arranged to partially overlap. For this reason, in this regard, the level of the first seat 6 can be lowered, and a passenger space can be secured.

In the present embodiment, in a planar view, the intake pipe 30, the cooling air supply duct 40, and the cooling air exhaust duct 41 are arranged to partially overlap. As a result, the intake pipe 30 and each of the ducts 40, 41 vertically overlap and therefore a piping space for the intake pipe 30, the cooling air supply duct 40, and the cooling air exhaust duct 41 can be easily secured. Since the intake pipe 30 and the ducts 40 and 41 serving as noise sources are close to each other, a noise insulating structure such as a structure in which the ducts are covered with a cover can be simplified.

Since a portion of the intake pipe 30 arranged in the console 24 is arranged above portions of the cooling air supply duct 40 and the cooling air exhaust duct 41 in the passenger space, a piping space can be easily secured again as described above, and a sound insulating structure can be simplified.

Since the surge tank 34 interposed in the middle of the intake pipe 30 is arranged above the cooling air supply duct 40 and the cooling air exhaust duct 41, the surge tank 34 insulates noise from the cooling air supply duct 40 and the cooling air exhaust duct 41. A space for arranging the surge tank 34 having a relatively large capacity can be secured. The console (projecting unit) 24 projecting upward from the first floor 8 as well as extending from the center portion in the width direction of the vehicle to the rear side in the front/rear direction of the vehicle, and the intake pipe 30, the cooling air supply duct 40, and the cooling air exhaust duct 41 are arranged below the console 24 to overlap the console 24 in planar view. For this reason, the console 24 can inhibit suction noise, exhaust noise, and the like from being transmitted to a passenger.

Since the console 24 communicates with the front chamber B, the passages can be arranged to extend from the engine unit 3 to the front chamber B, and the console 24 can be easily used as an engine arrangement space. 

1. A method of cooling electrical components of a vehicle including a continuously variable transmission comprising: providing an air intake passageway for communicating air from the ambient environment into said continuously variable transmission; providing an air exhaust passageway for communicating air from said continuously variable transmission to said ambient environment; providing a housing for electrical components having an air inlet and an air outlet; communicating said air outlet of said electrical component housing with said air intake passageway; directing air into said air inlet of said electrical component housing for cooling electrical components; directing air from said housing for electrical components to said continuously variable transmission via said air intake passageway; and directing air from said continuously variable transmission to said ambient environment through said air exhaust passageway. 